Malicious PDF — malware analysis report

Static analysis result for SHA-256 71ab0739f5492170…

MALICIOUS

PDF

70.6 KB Created: 2021-09-11 11:10:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 6513be2c0100eb8a277ef440045d2e26 SHA-1: 777974794cc2a1278a9e2f2c12df9c371dcfaaa7 SHA-256: 71ab0739f5492170814a1c24292cc94ece65637da11c8b484f12e6ccffde60fa
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. It contains a link farm with numerous URLs, many hosted on potentially disposable domains, suggesting a phishing or malware distribution scheme. The presence of external URIs and a link farm heuristic points towards an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://hydrogears.com/survey/userfiles/files/82152733753.pdf In PDF document text
    • http://hantechwelding.com/userfiles/file/2021090822085573499.pdfIn PDF document text
    • https://perfecthospitals.org/FCKeditor/file/kepureke.pdfIn PDF document text
    • http://idominjazz.com/fckeditor/userfiles/image/26226567117.pdfIn PDF document text
    • http://someteme.com/archivos/_20210902011706.pdfIn PDF document text
    • https://inverpalmas.com/aym_image/files/mukewabuxixebujober.pdfIn PDF document text
    • http://gzlmjx.com/data/home/bxu2343160066/htdocs/uploadfile/files/punufasejutixonoso.pdfIn PDF document text
    • https://swalaya.in/userfiles/file/17508563959.pdfIn PDF document text
    • https://peoplehelppeople.net/uploads/File/82161772639.pdfIn PDF document text
    • https://chicagoportablexray.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133f81dd3f8b---79841546504.pdfIn PDF document text
    • http://headlinesdinerla.com/uploads/files/7684347624.pdfIn PDF document text
    • http://www.dereformasenalicante.com/archivos/files/wewisowofefijoxunenun.pdfIn PDF document text
    • https://buildingexpertsdirectory.com/ckfinder/userfiles/files/nubewekifugolujexel.pdfIn PDF document text
    • http://adgroup.co/userfiles/file/toribejif.pdfIn PDF document text
    • https://rsvforum.com/userfiles/file/bopowefufakesofavujol.pdfIn PDF document text
    • http://webs123.com/userfiles/file/64465858065.pdfIn PDF document text
    • http://style4.allwebeasy.com/userfiles/files/60374528544.pdfIn PDF document text
    • https://sportuna.be/ckfinder/userfiles/files/besazejavudesakumazoke.pdfIn PDF document text
    • http://dienlanhhuubinh.com/upload/files/76148185190.pdfIn PDF document text
    • https://jsptti.com/ckeditor/ckfinder/userfiles/files/90377209640.pdfIn PDF document text
    • https://travelselection.us/wp-content/plugins/formcraft/file-upload/server/content/files/16137bbaf3ef5d---mowuwuwazelo.pdfIn PDF document text
    • https://www.cir.cloud/wp-content/plugins/formcraft/file-upload/server/content/files/1613520f89db17---56678256396.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=play+gta+4+online+freePDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b44b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB44B 16036 bytes
SHA-256: f2528ab191b798e5a13fe704e400fab941ef4b18c5b1d950e8a8b26e4d55c666
font_01_sfnt_off0000dd75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD75 10412 bytes
SHA-256: c24d20ab0967bdc6cd4a3a406ba57e975aa637f1b974495d29e912a719ce3e77
font_02_sfnt_off0000f541.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF541 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1